Method of making cut nails from flat strip stock



H. K. KELLY 3,130,425 METHOD OF MAKING CUT NAILS FROM FLAT STRIP STOCK April 28, 1964 2 Sheets-Sheet 1 Original Filed Dec. 3, 1959 v ooooo'oQ O O O O O O INVENTOR. H UBE RT LLY Hm-n03 April 28, 1964 H. K. KELLY 3, 3

METHOD OF MAKING CUT NAILS FROM FLAT STRIP STOCK Original Filed Dec. 3, 1959 2 Sheets-Sheet 2 ooooo W INVENTOR.

H UBERT K. EL-LY By wf w United States Patent 1 Claim. or. 10-34 This invention relates to a method of making nails.

The invention has as an object a method of making nails from unprocessed flat strip stock, the nails having notches at opposite side edges in proximity to the head end portion of the nails, the nails being produced in high volume economically by punch press operation and with a minimum waste of material.

In the drawings- FIGURE 1 is a side elevational view of a nail embodying my invention.

FIGURE 2 is an edgewise elevational view of the nail.

FIGURE 3 is a view consisting of an enlargement of the point end portion of the nail shown in FIGURE 1.

FIGURE 4 is an enlarged sectional view taken on line 4-4, FIGURE 1.

FIGURE 5 is a plan view of the strip of fiat stock from which the nails are formed, showing the rows of initial perforations and with a number of the nails outlined in dotted line.

FIGURE 6 is a view, similar to FIGURE 4, showing a series of the nails severed from one side of the strip.

FIGURE 7 is a view, similar to FIGURE 6, illustrating the arrangement with double width stock.

This application is a division of my copending application, Serial Number 857,157, now abandoned.

The nail produced by my method is rectangular in cross section and formed with a flat head surface 10 having parallel side edges 11. The body of the nail is formed with a notch 12 in each side edge, the notches 12 being positioned below the head end portion of the nail. The body side edges 13 converge downwardly from the notches 12 and terminate at the point end of the nail. The upper ends of the side edges 13 merge with the notches 12 at a point 14 which is spaced inwardly from the planes of the side edges 11 of the head portion, as indicated by the dotted line 15, FIGURE 1.

The point end of the nail is formed with a surface 16 extending normal .to the axis of the nail and the side surfaces 17 thereof. Preferably, the surface 16 is of concave form, with the ends of the chord, indicated by the line 18, of said concave surface terminating at the side edges 13, to form sharp chisel or shearing edges 20, see FIGURE 3. The side edges of the concave surface 16 terminate at the sides 17 of the nail to provide sharp corners 19, see FIGURE 4.

The nail is particularly suited for use in nail driving machines which are provided with an elongated magazine having a nail guideway for receiving :a supply of nails which are advanced along the guideway to the driving mechanism of the machine. The notches 12 provide for the reception of a pair of ribs formed in the nail guideway. The nails are usually secured together in stick form by means of a suitable adhesive. The notches thus provide an arrangement for suspending the nails in the magazine of the machine.

Referring to FIGURES 5 and 6 of the drawings, the nail is manufactured economically from a strip 20 of flat stock. The strip is formed with a row of apertures 21 extending along an edge of the strip but spaced inwardly therefrom, the spacing being comparable to the spacing of the notches 12 downwardly from the head end 10 of the nail. A similar row of apertures 22 is formed in the opposite edge portion of the strip. These apertures, however, are offset in a direction lengthwise of the strip so that the apertures 22 are positioned in a plane, indicated by the dotted line 23, FIGURE 5, extending transversely of the strip and medial of the apertures 21. The apertures 21 and 22 are spaced apart in a direction lengthwise of the strip comparable to the spacing between the notches 12 in the finished nail.

The nails are blanked, or severed, from the strip 20, by severing inwardly from each side edge of the strip, the area between the apertures 21, 22, the blank terminating at the intermediate aperture at the opposite side of the strip. The blanking, or severing, of the nails from the strip is preferably performed by a progressive die, which is formed with punches for producing the apertures 21, 22, and with a punch having an outline comparable to the finished nail. This punch may be positioned in the die to remove, or sever, nails from the upper portion of the strip, as viewed in FIGURES 5 and 6. A third punch of the die is simply formed with a short shear edge to sever the nails from the opposite, or lower, side of the strip, this severance only consisting in separating the head portions of the nails remaining in the strip. For example, in FIGURE 6, alternate nails have been blanked from the strip, from the upper portion thereof, leaving in the lower portion of the strip a series of nails attached only by their head portions to form the comb effect seen in FIGURE 6. The third punch severing the nails from the comb arrangement at the edge 11 of the head portion of the nails.

The perforation of the strip 20 with apertures 21, 22, accordingly not only provides for the notches 12 of the finished nail, but also the concave point end surface 16. When out nails are blanked from strip stock in conventional manner, the surface of the point end of the nails merges with the side and edge surfaces of the nail body on a radius, with the result that sharp corners are not provided at the point end of the nail for the effective shearing of the wood fibers. is due partially to the extended length of the shear line in blanking the nail from the strip which requires an overall high pressure to be exerted by the punch and die, causing greater deformation of the stock. The same situation prevails when the nails are formed from rod stock by swedging dies. The apertures 21, 22, are preferably of circular form and, due to their relatively small dimension, the punching of these apertures results in a sharp edge or corner at the top and bottom surfaces of the strip and therefore, at the side surfaces 17 of the finished nail. Furthermore, the circular apertures provide for the concave point end surface 16 having its sharp chisel ends 18. These sharp corners and chisel edges result in cleanly severing the wood fibers, whereby the nail is more easily driven and retains greater holding power in the wood.

It will be obvious the nail production may be doubled by using stock wide enough to provide two joined strips, as shown in FIGURE 7. The same arrangement and process is used. In this instance the die structure is formed with an additional set of punches for operating simultaneously to form the double comb arrangement with the result of doubling the nail output upon each stroke of the press.

It will be observed by my method of forming the nail, the only Waste of the strip stock is in the form of the slugs punched therefrom in the formation of the apertures 21, 22.

What I claim is:

The method of forming nails having notches in the side edges thereof below the head end of the nail and having a body portion tapering to a point end, the method consisting in forming a flat strip of metal with a row of uniof thenail, said apertures being spaced in a-gdire'ction "lengthwise of the strip a distance equal 'to'the spacing between the notches of the nail, each row of apertures being spaced from: the opposite edge adjacent the opposite row of apertures a distance comparable to the length of the nail, arranging the apertures in one row in planes extending transversely of the strip medial of the apertures in the opposite row to provide nail forming portions extending transversely of the strip and tapering toward the point end, and alternate nail forming portions extending in opposite direction to the intermediate nail forming portions with the point ends of the nails terminating at said apertures, and severing the nail forming portions from the strip.

References Cited in the file of this patent UNITED STATESPATENTS 1,442,969 Pope Jan. 23, 1923 1,981,869 McFaul Nov. 27, 1934 2,630,175 Diokerman Mar. 3, 1953 

